The Spanish Tax Agency (Agencia Tributaria) has recently announced amendments to certain VAT return forms, specifically forms 303, 322, 353 and 390, as well as to the Immediate Supply of Information (SII) system. The purpose of these changes is to adapt the forms to the new regulations applicable to supplies of petrol, diesel and biofuels, which introduce an obligation to guarantee the payment of VAT in certain cases.
Below we explain what has changed in the VAT forms, who is affected by these amendments and which aspects should now be reviewed.
Why have these VAT forms been amended?
These amendments follow the definitive abolition of the regime for warehouses other than customs warehouses (DDA) for certain energy products. Under the new regulations, when biofuels, diesel or petrol are removed from a tax warehouse, the last depositor of the product, or the warehouse keeper where it is also the owner of the goods, must guarantee the payment of the VAT corresponding to the subsequent supply, provided that such supply is taxable and not exempt.
The aim of this measure is to strengthen control over the tax in this type of transaction and to prevent risks to tax collection.
Who is affected by these amendments?
These amendments mainly affect those involved in transactions involving petrol, diesel and biofuels that are removed from tax warehouses for subsequent supply on the domestic market.
In particular, they affect:
- Companies operating in the fuel sector, whether as depositors, distributors or tax warehouse keepers.
- The last depositor of the product at the time it is removed from the tax warehouse or, where applicable, the warehouse keeper when it is also the owner of the product.
- Companies subject to the SII that issue invoices for this type of supply, which must correctly identify these transactions in their VAT record books.
Operators with the status of Authorised Economic Operator (AEO) or trusted operator are excluded from the obligation to guarantee the VAT, although they must still take into account the formal changes introduced in the VAT forms and records.
What does the obligation to guarantee VAT consist of?
The VAT guarantee may be provided in two ways:
- By means of a guarantee, issued by a credit institution, financial institution or insurance company.
- By means of a VAT payment on account, which acts as an advance payment of the tax and may subsequently be deducted in the VAT return for the period in which the subsequent supply is declared.
This obligation does not apply where the operator holds the status of Authorised Economic Operator (AEO) or trusted operator, thereby reducing the administrative burden for those meeting the relevant requirements.
Main changes to forms 303, 322, 353 and 390
To reflect this new system, the VAT return forms now include new specific boxes for reporting the VAT payment on account linked to these fuel supplies. In addition, a new indicator has been added to the identification section to state whether the taxpayer is entitled to deduct the amount paid.
These adjustments affect both periodic VAT returns and the annual VAT summary return (form 390), ensuring consistency in the information reported throughout the financial year.
When does these changes apply?
The amendments are already in force and apply for the first time:
- To forms 303, 322 and 353 corresponding to February 2026 or the second quarter of 2026, depending on the filing frequency
- To form 390 for the 2026 tax year.
- To SII records relating to transactions carried out from 1 February 2026 onwards.
What should be reviewed?
Although these are very specific changes, companies and advisers are advised to review whether they carry out affected transactions, adapt their internal procedures and management systems, and ensure the correct completion of the new fields included in the VAT forms.
At LEIALTA, we support companies and professionals in reviewing their tax obligations, with a preventive approach focused on legal certainty.
